Thermal storage lid

[0002] The present invention relates to a thermal storage lid for a storage container, and more particularly to a lid having a thermal energy storing material located therein.

[0003] Thermal energy storage packs are generally known for use in maintaining the contents of a storage container in a heated or cooled state. For example, frozen thermal packs are pre-filled with a thermal energy storage material which can be frozen and then placed in a thermal energy storage container, such as a cooler, in order to maintain the cooler contents such as food storage containers, in a cold state for a predetermined time period. Such thermal energy materials generally have 10-15 times the thermal capacity of frozen water and therefore maintain the cooler contents in a cold state for an extended period of time in comparison to ice alone. Such cold packs can be reused numerous times by refreezing them between use, and also avoid the problem of melting liquid contacting the items in the cooler. However, it is not always convenient to fit a cold pack in a cooler or other containers in addition to the various food storage containers placed therein.

[0004] Energy storage materials which maintain heat are also known which can be preheated in a microwave or through other means, and then placed in a thermal energy storage box in order to provide heat within the box to keep food storage containers in the box warm for a predetermined time period.

[0005] These heat or cold packs generally come in predetermined sizes which are not always suitable for use with a particular cooler or box, depending upon the articles or food storage containers also being placed therein.

[0006] The present invention provides a thermal storage lid for a storage container. The lid includes a first panel having an attachment element located around a periphery thereof. The attachment element is adapted to engage a complementary container attachment element. A second panel is offset from the first panel and has a peripheral edge connected to the first panel to form a compartment generally coextensive with the second panel. A thermal storage material is located in the compartment.

[0007] In another aspect of the invention, the thermal storage lid is provided with a storage container to which the thermal storage lid is removably connected.

[0008] The foregoing summary as well as the following detailed description of the preferred embodiments of the invention will be more easily understood if reviewed in conjunction with the appended drawings. In the drawings:

[0009] FIG. 1 is a cross-sectional view through a thermal storage lid in accordance with the invention located on a container.

[0010] FIG. 2 is a greatly enlarged detail, partially broken away, of the thermal storage lid of FIG. 1.

[0011] FIG. 3 is a bottom view of the thermal storage lid shown in FIG. 1.

[0012] FIG. 4 is a greatly enlarged detail, similar to FIG. 2, of a second embodiment of a thermal storage lid.

[0013] Certain terminology is used in the following description for convenience only and is not considered limiting. The words “lower” and “upper” designate directions in the drawings to which reference is made. This terminology includes the words specifically noted above, derivatives thereof, and words of similar import. Additionally, the terms “a” and “one”, as used in the claims and in the corresponding portions of the specification, are defined as including one or more of the referenced item unless specifically noted.

[0014] Referring now to FIGS. 1-3, a first embodiment of a thermal storage lid 10 for a container 12, which is preferably a food storage container, is shown. The lid 10 is preferably made of a polymeric material, such as PET, PVC, PPC or any other suitable material. The lid 10 includes a first panel 20 with an attachment element 22 located around a periphery thereof. The attachment element 22, which is shown in more detail in FIG. 2, is preferably a form locking connection which can be snapped into engagement with a complementary container attachment element 24. The attachment element 22 is preferably formed with a downwardly offset section 26 having an outwardly directed bump that can be engaged in a complementary recess in the container attachment element 24. This arrangement is a generally well known snap-type connection arrangement for food storage container lids. However, other suitable attachment elements may be utilized in accordance with the invention and the container can be of various and different types.

[0015] A second panel 30 is offset from the first panel 20 and includes a peripheral edge 32 which is connected to the first panel to form a compartment 34 generally coextensive with the second panel 30. Preferably, the second panel 30 is heat sealed to the offset portion 26 of the attachment element 22 of the first panel 20. However, other suitable connecting means, such as an adhesive or a solvent weld may also be utilized. Additionally, as shown in FIG. 2, the peripheral edge 32 of the second panel 30 faces toward a downwardly extending leg 28 around the periphery of the first panel 20 such that the peripheral edge 32 of the second panel 30 is not exposed during normal use. This results in a generally seamless appearance since the seam is generally out of any line of sight.

[0016] A thermal energy storage material 40 is located in the compartment 34. Preferably, the thermal energy storage material 40 is located in a sealed pouch 42 that is placed in the compartment 34 prior to sealing the second panel 30 to the first panel 20. The compartment 34 is preferably sealed to prevent the ingress of moisture or any other contaminants in order to allow the lid 10 to be easily cleaned for further use. Alternatively, the lid 10 may be provided as a disposable lid for use in connection with disposable containers.

[0017] In the preferred embodiment, the thermal energy storage material is in the form of a gel which can receive repeated cycles of freezing and thawing in order to provide a cold storage lid. Heat storing materials may also be utilized such that the lid can be placed in a microwave oven in order to heat the thermal energy storage material 40 prior to placing it on a container in order to keep the container contents warm.

[0018] In order to achieve a novel look, preferably the first and second panels are formed of transparent or translucent material so that the thermal energy storage material 40 can be seen. The thermal energy storage material may also be translucent or transparent in appearance. In addition, the thermal energy storage material and/or the pouch 42 in which it is located may be colored in any one of various colors. For example, for a cold storage thermal energy storing material 40, a blue color could be provided which may be translucent. For a hot material a red or pink transparent or translucent color could also be provided.

[0019] In use, the lid 10 is charged with thermal energy, such as by placing in a freezer in order to cool the thermal energy storage material 40 or by placing in a microwave and heating in order to charge the thermal energy storage material 40 with heat energy. The lid 10 is then snapped onto the container 12 by engaging the attachment element 22 located around the periphery of the lid 10 with the complementary attachment element 24 on the container 12. For cooling applications, the container 12 is cooled via heat energy from the container being absorbed by the thermal energy storage material 40 in order to maintain the contents of the container 12 in a cooled state. For heating applications, the thermal energy storage material 40 radiates heat which maintains the contents of the container 12 in a heated condition.

[0020] Referring now to FIG. 4, a second embodiment of the thermal energy storage lid 110 is shown. The lid 110 is similar to the lid 10 except that the energy storage material 142 is located directly between the first panel 120 and second panel 130 which is heat sealed around its periphery 132 to the first panel 120.

[0021] While the preferred embodiments of the invention have been described in detail, the invention is not limited to the specific embodiment described above, which should be considered as merely exemplary. Further modifications and extensions of the present invention may be developed and all such modifications are deemed to be within the scope of the present invention as defined by the appended claims.